A 20-year-old woman presented to the emergency room with sudden onset of cold, pale fingers, and discolored spots in the fingertips of the left hand (Figure 13-1). The patient’s medical history was significant for fatigue and weakness of the left hand for about 1 year. She attributed these symptoms to overuse at work as a nursing assistant at the hospital. Her physical examination was significant for discoloration and splinter hemorrhages of the fingers. She had palpable radial and ulnar pulses. With overhead left arm elevation, the patient complained of pain in the entire left upper extremity. The workup included a chest x-ray and left upper extremity angiogram. The chest x-ray showed bilateral cervical ribs (Figure 13-2). Angiogram confirmed the presence of a subclavian artery aneurysm with partial thrombosis (Figure 13-3). Her hand angiogram showed evidence of embolic disease to her digits (Figure 13-4).

The final diagnosis was of thoracic outlet syndrome (TOS) with arterial involvement complicated by subclavian arterial aneurysm and distal microembolization.

• 
  

  Arterial involvement is the least common form of TOS.

  
  
• 
  

  Most patients with symptoms of arterial TOS are young, active adults.

  
  
• 
  

  The mean age in most published series is 37 years, with a similar proportion of men and women reported.¹

  
  
• 
  

  The condition appears to be related to bony abnormalities or trauma in nearly every circumstance.

  
  
• 
  

  No familial predisposition has been described.¹